WASHINGTON, July 2 Relentless heat gripped much
of the eastern United States for a fourth straight day on
Monday, with nearly 2 million homes and businesses without power
after violent storms and soaring temperatures killed at least 18
people.

Power companies warned it could take several days to restore
electricity completely in some areas as much of the United
States sweltered in a heat wave. On Sunday, 288 temperature
records were set nationwide.

"Above-normal temperatures will continue to affect a large
portion of the country from the northern Plains to the
Mid-Atlantic over the next few days," the National Weather
Service said.

Severe thunderstorms, strong winds and hail ripped down
trees and power lines in northern Minnesota, knocking out the
phone system in the city of Bemidji and soaking Duluth,
authorities said.

"It's quite a big wind event," said Dave Kellenbenz of the
National Weather Service in nearby Grand Forks, North Dakota.

Storms also struck in southern Illinois, Kentucky and
Tennessee, the weather agency said.

Many areas will see temperatures from 90 Fahrenheit (32
Celsius) to more than 100 F (37.7 C), it said in a statement.
Excessive heat warnings and advisories remained over much of the
mid-Mississippi Valley and southern states.

Emergencies were declared in Maryland, Ohio, Virginia, West
Virginia and Washington because of damage from a rare "super
derecho" storm packing hurricane-force winds across a 700-mile
(1,100-km) stretch from the Midwest to the Atlantic Ocean.

Nearly 2 million homes and businesses from Illinois to New
Jersey were still without power, with the biggest concentration
in the Washington area.

With power lines down across the region, the U.S. government
told federal workers in the Washington area they could take
unscheduled leave or work from home on Monday and Tuesday.

Two of the largest property insurers, USAA and Nationwide,
said they had received more than 12,000 claims in total from the
weekend storms. Most were for house damage.

The storms capped a costly June for insurers, which were
already facing losses of at least $1 billion from a hailstorm
that ripped through Dallas.

DAMAGE TO POWER GRIDS

Thunderstorms and high winds battered eastern North Carolina
on Sunday afternoon, causing three more deaths on top of at
least 15 from deadly storms and heat in several states.

About 93,000 customers in northeastern Illinois of
Commonwealth Edison, a unit of Exelon Corp, were without
power from the storms that brought wind gusts of up to 90 miles
per hour (145 km per hour).

Utilities in Ohio, Virginia and Maryland described damage to
their power grids as catastrophic.

FirstEnergy utilities in states from Ohio to West
Virginia had about 194,400 customers without power.

Pepco, which serves Washington and much of its
suburbs in Maryland and Virginia, reported about 201,900
customers without power.

Baltimore Gas & Electric said about 213,000 customers
remained affected. Almost 1,200 utility workers from 12 states
and Canada are helping restore power or are on their way to
central Maryland, the company said.

Storms killed six people in Virginia and left more than 1
million customers without power. Two people were killed in
Maryland, officials said.

A falling tree killed two cousins, aged 2 and 7, in New
Jersey. Heat was blamed for the deaths of two brothers, ages 3
and 5, in Tennessee who had been playing outside in temperatures
reaching 105 F (41 C).

St. Louis reported three heat-related deaths over the
weekend. All were elderly and had air conditioners not in use.

Meanwhile, soybean and corn crops in the U.S. Midwest are
expected to get hit hard by the unrelenting heat and dryness.
Corn, which is entering its critical pollination or reproductive
stage of development, is seen as especially vulnerable.

"We're still looking at a scenario providing below-average
rainfall for at least the next 10 days," said agricultural
meteorologist John Dee of Global Weather Monitoring.

AccuWeather, a weather forecaster, said the "super derecho"
storm that caused the widespread damage had raced 700 miles
(1,260 km) from northern Indiana to the Atlantic coast in 12
hours.

A derecho - Spanish for "straight" - is a long-lasting wind
storm that accompanies fast-moving thunderstorms or showers,
AccuWeather said. The most powerful derechos are called "super
derechos," described by AccuWeather as a "land hurricane."

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